Several studies have been conducted into scalp hair, in particular into the cause of the color and thickness, but also baldness. All these properties of the hair are caused by certain genes. Many of those genes work together to express themselves. For example, five different genes are active for the color of the hair, which together determine the hair color. The genes probably don’t work on their own, but do so under the influence of other factors. What exactly these are has yet to be explored.
What about the graying of the hair? There is an interesting development in hair graying research. The gene that causes hair to turn gray has recently been identified. This gene, IRF4, also aids in hair color determination and regulates pigmentation in the hair, as well as in the skin and eyes. The gene regulates and produces melanin. When too little melanin is produced, the pigment in the hair will slowly disappear, making the hair gray. But how come the hair (usually) only turns gray at a later age and not when we are young?
What can we do with this knowledge?
There are two applications of this knowledge that will have a major impact. The most obvious is that the cosmetic industry is probably very interested in knowing what causes hair to turn gray at some point. What they would rather know is what ensures that people usually do not get gray hair in the younger years. More research needs to be done to precisely determine this process. With this knowledge, products can be developed that prevent or delay the graying of the hair.
Another application, which is somewhat less obvious, is the use of this knowledge in forensic investigations. The data from the DNA can be used to create a visual image of, for example, the perpetrator of a crime. If there is an image of it, the detection will be easier.
View here the full survey .